Osama bin Laden's death helped supercharge traffic to UK newspaper websites in May, with market leader Mail Online surging ahead to a new record of nearly 80 million monthly unique users.

Guardian.co.uk, the second most popular UK newspaper website, also registered a huge traffic boost in May, topping 50 million monthly uniques for the first time, while Telegraph.co.uk, Independent.co.uk and Mirror Group Digital all saw double digital month-on-month growth.

However, once again it was Mail Online that surged ahead of the pack, with a 21.4% jump in daily unique users compared with April to 4,365,716, according to the latest Audit Bureau of Circulations Electronic figures published on Thursday. Mail Online was up by nearly 770,000 daily uniques compared with April's figure of just under 3.6 million.

Mail Online's monthly unique users grew by just over 21% month on month – from 63.75 million – to 77,250,993 in May.

Guardian.co.uk increased its daily uniques by nearly 18% month on month to a new high of 2,827,677, while the monthly figure for May was 51,383,937.

The Guardian News & Media website network, which incorporates content from the Guardian and Observer and includes MediaGuardian.co.uk, had just under 49.2 million monthly unique users when it last reported an official ABCe monthly figure for March. Guardian.co.uk reports monthly uniques every alternate month.

Independent.co.uk reported a 15.2% month-on-month lift in average daily users in May, to 675,129, as it closes the gap on Mirror Group Digital's network of websites. Monthly users rose 18% in the same period.

The MGD sites, including mirrorfootball.co.uk and 3am.co.uk, boosted daily online traffic by 12% last month, to 706,838 users. Monthly users are up 11.75% in the same period.

Telegraph.co.uk also got a boost from the news-heavy month, increasingly daily average users by 13.25% to 2,188,745. The Telegraph website saw a 14% lift in monthly users over the same period.

The Daily Mail & General Trust website network, which incorporates content from the Daily Mail and Mail on Sunday, also became the first UK newspaper to publish ABCe monthly figures for its iPhone app, revealing that 168,507 people used it to access Mail Online in May. The daily average figure for iPhone app users was 62,125.

Since the app was launched in October, it has been downloaded more than 315,122 times. Available through the UK iTunes store, the Mail Online app is free for 60 days. Users can then continue to access Mail Online for free with ads, or pay £4.99 for six months or £8.99 for a year without advertising.

Mail Online

Daily average browsers: 4,365,716

Month-on-month change: +21.4%

Year-on-year change: +82.66%

Monthly browsers: 77,259,993

Monthly change: +21.17%

theguardian.com

Daily average browsers: 2,827,677

Month-on-month change: +17.46%

Year-on-year change: +40.66%

Monthly browsers: 51,383,937

Monthly change: N/A

Telegraph.co.uk

Daily average browsers: 2,188,745

Month-on-month change: +13.25%

Year-on-year change: +31.54%

Monthly browsers: 43,796,963

Monthly change: +14.05%

Mirror Group Digital

Daily average browsers: 706,838

Month-on-month change: +12%

Year-on-year change: +40.7%

Monthly browsers: 15,766,729

Monthly change: +11.75%

Independent.co.uk

Daily average browsers: 675,129

Month-on-month change: +15.2%

Year-on-year change: +40.08%

Monthly browsers: 15,225,779

Monthly change: 18.47%

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